An organic electroluminescent device is a device which has a basic structure such that a light emitting layer containing a light emitting material is sandwiched between a hole transport layer and an electron transport layer, and further an anode and a cathode are attached outside thereof, and which utilizes emission of light (fluorescence or phosphorescence) associated with excitation deactivation which occurs by recombination of holes and electrons injected to the light emitting layer, and it is applied to a display, etc. Incidentally, there may be a case where the hole transport layer is divided into a hole transport layer and a hole injection layer, where the light emitting layer is divided into an electron blocking layer, a light emitting layer and a hole blocking layer, or where the electron transport layer is divided into an electron transport layer and an electron injection layer.
Although recent organic electroluminescent devices have been gradually improved, it is still desired to improve luminous efficiency characteristics, drive voltage characteristics and long service life characteristics.
Organic electroluminescent devices have been known wherein as electron-transporting materials, various triazine compounds and pyrimidine compounds are used (for example, see Patent Documents 1, 2, 3 and 4), but also for such devices, further improvement of long service life has been desired.